Scenario One: A general election in December
If Leo Varadkar and Fianna Fáil leader Micheál Martin fail to reach agreement, and if the Taoiseach stands foursquare behind his Tánaiste Frances Fitzgerald, then an election is inevitable.
The first thing that will happen is the dissolution of the Dáil. This is provided for under Article 13.2 of the Constitution. The Taoiseach is required to go to Áras an Uachtaráin to advise the President to dissolve the Dáil.
The President then signs a proclamation giving effect to the dissolution. The Constitution provides that a general election must be held within 30 days.
Under the Electoral Acts there is a more specific requirement that polling must take place within 18 and 25 days, not including Sundays or bank holidays. The decision on polling day will be taken by the Minister for Housing.
The big difficulty is that if the Taoiseach waits until next Tuesday, the earliest he could hold an election would be Thursday, December 18th. With counts taking two days, it could mean the result would be announced on December 20th.
If the Taoiseach were to make the decision Friday, November 24th, and not wait until the confidence vote is taken, it is possible polling day would be December 15th.
At the other extreme, the last day a vote could take place would be December 28th.
Scenario Two: A January election
The Taoiseach has privately raised the possibility of a January election to his colleagues. That would involve some mechanism that would allow polling day to be delayed.
But if the Fianna Fáil and Sinn Féin motions proceed the Government will have lost a vote of confidence. Once that occurs the Taoiseach will have no choice but to seek dissolution of the Dáil. And the Constitution is clear on that: it has to happen within 30 calendar days.
However, the President has powers under article 13 of the Constitution to refuse the dissolution of the Dáil. It states: “The President may in his absolute discretion refuse to dissolve Dáil Éireann on the advice of a Taoiseach who has ceased to retain the support of a majority in Dáil Éireann.”
In the early 1980s, when a Fine Gael government fell, an attempt was made by senior Fianna Fáil members to reach then President Patrick Hillery by telephone. They wanted to request him to use those powers in order to allow Charles Haughey form a government.
The alleged telephone call made by Brian Lenihan senior to the Áras became the main controversy of the 1990 presidential election after he denied making the call. Lenihan was beaten in the election by Mary Robinson. He was also fired as minister for defence by Charles Haughey after coalition partners Progressive Democrats demanded it.
Scenario Three: Frances Fitzgerald steps down
This is the only realistic scenario that will avoid an election in December or January. It would push out the date to spring.
The rhetoric from all sides has hardened so much this week that is looking increasingly less likely. However, there is a possibility she may resign at her own volition for the greater good despite the protestations of the Taoiseach, who has said he does not want her to resign.
That would allow Fianna Fáil to withdraw its motion of confidence from the Dáil agenda on Wednesday, allowing the confidence and supply agreement to be restored.
Even if it is restored there is general agreement between both main parties there has been a big breach in trust, and that a general election will follow in a comparatively short space of time.
Such a scenario would allow Sinn Féin a more orderly transition of leadership. If there is a December election it might mean that Mary Lou McDonald would act as party leader, while Gerry Adams remained in situ as party president.